Single needle blood fractionation system having adjustable recirculation through filter

Claim 2

A blood fractionation system for separating a blood fraction from whole blood, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle for alternately drawing and returning whole blood from a donor; an intermediate fluid reservoir; separating means for separating the blood fraction from whole blood; first fluid conveyance means including an inlet pump for conveying fluid from said donor conduit through said separation means to said reservoir; second fluid conveyance means including a return pump responsive to the volume in said reservoir reaching a predetermined maximum level for conveying whole blood from said reservoir to said donor interface conduit to reduce the volume in said reservoir to a predetermined minimum level; and said second pump rate being set relative to said first pump rate whereby said operation of said second fluid conveyance means a selected portion of the flow from said reservoir is caused to recirculate through said separation means.

Claim 3

A blood fractionation system as defined in claim 1 wherein said second fluid conveyance means are responsive to the weight of said intermediate reservoir.

Claim 4

A blood fractionation system as defined in claim 2 wherein said second fluid conveyance means include a weight transducer for providing an output signal indicative of the weight of said intermediate reservoir.

Claim 5

A blood fractionation system as defined in claim 3 wherein said output signal is an analog signal and said second fluid conveyance means include means for comparing said signal with predetermined maximum and minimum reference levels.

Claim 6

A blood fractionation system as defined in claim 1 wherein the rates of said inlet and return pumps are operator-adjustable.

Claim 7

A blood fractionation system as defined in claim 1 wherein said inlet and return pumps are each peristaltic-type pumps.

Claim 8

A blood fractionation system as defined in claim 1 wherein the volume of said first fluid conveyance means is substantially equal to or greater than the volume of whole blood returned from said reservoir upon operation of said second fluid conveyance means.

Claim 9

A blood fractionation system as defined in claim 7 wherein said first fluid conveyance means include a fluid mixing chamber upline of said separation means having a volume substantially equal to or greater than the volume of whole blood returned from said reservoir upon a single operation of said second fluid conveyance means. 1

Claim 10

A blood fractionation system as defined in claim 1 wherein said separation means is a membrane type filter.

Claim 11

A blood fractionation system as defined in claim 9 wherein said filter is a hollow fiber type filter.

Claim 12

A blood fractionation system as defined in claim 1 wherein said second fluid conveyance means include a bubble trap and fluid absence detector.

Claim 13

A single needle blood fractionation system for separating a blood fraction from whole blood, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; T means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit connecting said intermediate fluid reservoir and said donor interface conduit; an inlet pump for pumping fluid through said first conduit to said reservoir; a return pump for pumping fluid from said intermediate reservoir through said second conduit; system control means responsive to the volume of fluid in said intermediate reservoir for initiating operation of said return pump in response to said volume reaching a predetermined maximum level, and for terminating operation of said return pump upon said volume reaching a predetermined minimum level; and the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator selectable portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter.

Claim 14

A single needle blood fractionation system for separating a blood fraction from whole blood, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; T means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit connecting said intermediate fluid reservoir and said donor interface conduit; an inlet pump for pumping fluid through said first conduit to said reservoir; a return pump for pumping fluid from said intermediate reservoir through said second conduit; system control means responsive to the volume of fluid in said intermediate reservoir for initiating operation of said return pump in response to said volume reaching a predetermined maximum level, and for terminating operation of said return pump upon said volume reaching a predetermined minimum level; and the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator selectable portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter.

Claim 15

A blood fractionation system as defined in claim 12 wherein said system control means are responsive to the weight of said intermediate reservoir.

Claim 16

A blood fractionation system as defined in claim 13 wherein said system control means include an electrical weight transducer providing an output signal indicative of the weight of said reservoir.

Claim 17

A blood fractionation system as defined in claim 14 wherein said output signal is an analog signal, and said system control means include means for comparing said output signal with predetermined maximum and minimum reference levels.

Claim 18

A blood fractionation system as defined in claim 12 wherein the rates of said inlet and return pumps are operator-adjustable.

Claim 19

A blood fractionation system as defined in claim 12 wherein said inlet and return pumps are each peristaltic-type pumps.

Claim 20

A blood fractionation system as defined in claim 12 wherein the volume of said first conduit is substantially equal to or greater than the volume of whole blood returned from said reservoir upon operation of said return pump.

Claim 21

A blood fractionation system as defined in claim 18 wherein said first conduit includes an in-line fluid mixing chamber upline of said filter having a volume substantially equal to or greater than the volume of whole blood returned from said reservoir upon a single operation of said return pump.

Claim 22

A blood fractionation system as defined in claim 12 wherein said filter is a membrane type filter.

Claim 23

A blood fractionation system as defined in claim 20 wherein said filter is a hollow fiber type filter.

Claim 24

A blood fractionation system as defined in claim 12 wherein said second fluid conduit means include a bubble trap and a fluid absence detector.

Claim 25

A blood fractionation system as defined in claim 12 wherein said separated blood fraction comprises plasma.

Claim 26

A single needle blood fractionation system for separating a blood fraction from whole blood, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; j means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit conneeting said intermediate fluid reservoir and said donor interface conduit; an inlet pump for pumping fluid through said first conduit to said reservoir; a return pump for pumping fluid from said intermediate reservoir through said second conduit; system control means responsive to the volume of fluid in said intermediate reservoir for initiating operation of said return pump in response to said volume reaching a predetermined minimum level, thereby causing a predetermined volume of filtered fraction-depleted blood to be pumped from said intermediate reservoir; the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator selectable portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter; and means including an inline mixing chamber disposed in said first conduit upline of said filter and having a volume substantially equal to or greater than said predetermined volume of filtered blood pumped from said intermediate reservoir whereby the portion of said pumped filtered blood advanced through said first conduit is mixed with blood previously advanced in said first conduit prior to initiating operation of said return pump.

Claim 27

A single needle blood fractionation system for separating a blood fraction from whole blood, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; j means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit conneeting said intermediate fluid reservoir and said donor interface conduit; an inlet pump for pumping fluid through said first conduit to said reservoir; a return pump for pumping fluid from said intermediate reservoir through said second conduit; system control means responsive to the volume of fluid in said intermediate reservoir for initiating operation of said return pump in response to said volume reaching a predetermined minimum level, thereby causing a predetermined volume of filtered fraction-depleted blood to be pumped from said intermediate reservoir; the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator selectable portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter; and means including an inline mixing chamber disposed in said first conduit upline of said filter and having a volume substantially equal to or greater than said predetermined volume of filtered blood pumped from said intermediate reservoir whereby the portion of said pumped filtered blood advanced through said first conduit is mixed with blood previously advanced in said first conduit prior to initiating operation of said return pump.

Claim 28

A blood fractionation apparatus for use in conjunction with a fluid flow system having a phlebotomy needle, a flow-through filter, an intermediate fluid reservoir, a first fluid conduit connecting the phlebotomy needle, filter and reservoir, and a second fluid conduit connecting the reservoir and the phlebotomy needle, comprising: an inlet pump for pumping whole blood from the phlebotomy needle through the filter to the reservoir; a return pump for pumping fluid from the reservoir to the phlebotomy needle; system control means responsive to the volume of fluid in the reservoir for initiating operation of said return pump upon filtered fluid in the reservoir reaching a maximum predetermined level, and for terminating operation of said return pump upon the fluid reaching a predetermined minimum volume; and the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator-selectable portion of the output of said return pump is caused to recirculate through said inlet pump and said filter and the remaining portion of said output is caused to be returned through the phlebotomy needle to the'donor.

Claim 29

A blood fractionation apparatus for use in conjunction with a fluid flow system having a phlebotomy needle, a flow-through filter, an intermediate fluid reservoir, a first fluid conduit connecting the phlebotomy needle, filter and reservoir, and a second fluid conduit connecting the reservoir and the phlebotomy needle, comprising: an inlet pump for pumping whole blood from the phlebotomy needle through the filter to the reservoir; a return pump for pumping fluid from the reservoir to the phlebotomy needle; system control means responsive to the volume of fluid in the reservoir for initiating operation of said return pump upon filtered fluid in the reservoir reaching a maximum predetermined level, and for terminating operation of said return pump upon the fluid reaching a predetermined minimum volume; and the rate of said return pump being adjustable relative to the rate of said inlet pump whereby upon operation of said return pump an operator-selectable portion of the output of said return pump is caused to recirculate through said inlet pump and said filter and the remaining portion of said output is caused to be returned through the phlebotomy needle to the'donor.

Claim 30

A blood fractionation apparatus as defined in claim 25 wherein said system control means are responsive to the weight of said reservoir.

Claim 31

A blood fractionation a-paratus as defined in claim 26 wherein said system control means include an electrical weight transducer providing an output signal indicative of the weight of the intermediate reservoir.

Claim 32

A blood fractionation apparatus as defined in claim 25 wherein said inlet pump and said return pump each comprise positive displacement pumps.

Claim 33

A blood fractionation apparatus as defined in claim 28 wherein said inlet and return pumps each comprise peristaltic-type pumps.

Claim 34

A disposable flow system for performing a blood fractionation procedure in conjunction with blood fractionation apparatus of the type having an inlet pump, a return pump, and system control means responsive to the volume of fluid in an associated fluid reservoir for initiating operation of said return pump in response to said volume reaching a predetermined maximum leve, and for terminating operation of said return pump upon said volume reaching a predetermined minimum level, the rate of the return pump being adjustable relative to the rate of the inlet pump, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit connecting said intermediate fluid reservoir and said donor interface conduit; and said intermediate fluid reservoir being adapted for association with said system control means, whereby upon operation of said return pump an operator selected portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter.

Claim 35

A disposable flow system for performing a blood fractionation procedure in conjunction with blood fractionation apparatus of the type having an inlet pump, a return pump, and system control means responsive to the volume of fluid in an associated fluid reservoir for initiating operation of said return pump in response to said volume reaching a predetermined maximum leve, and for terminating operation of said return pump upon said volume reaching a predetermined minimum level, the rate of the return pump being adjustable relative to the rate of the inlet pump, comprising: means including a donor interface conduit adapted for connection to a phlebotomy needle and alternately operable in forward and reverse flow for alternately receiving and returning blood from a donor; an intermediate fluid reservoir; means including a first conduit connecting said donor conduit to said intermediate fluid reservoir; means including a flow-through filter disposed in said first conduit for separating the desired blood fraction from whole blood flowing through said filter; means including a second conduit connecting said intermediate fluid reservoir and said donor interface conduit; and said intermediate fluid reservoir being adapted for association with said system control means, whereby upon operation of said return pump an operator selected portion of the filtered blood in said second conduit is caused to recirculate through said first conduit and said filter.

Claim 36

A disposable flow system as defined in claim 30 wherein the volume of said first conduit is substantially equal to or greater than the volume of whole blood returned from said reservoir upon operation of said return pump. :

Claim 37

A disposable flow system as defined in claim 31 wherein said first conduit includes an in-line fluid mixing chamber upline of said filter having a volume substantially equal to or greater than the volume of whole blood returned from said reservoir upon a single operation of said return pump.

Claim 38

A disposable flow system as defined in claim 30 wherein said filter is a membrane type filter.

Claim 39

A disposable flow system as defined in claim 33 wherein said filter is a hollow fiber type filter.

Claim 40

A disposable flow system as defined in claim 30 wherein said second fluid conduit includes a bubble trap.

Claim 41

A blood fractionation system comprising: a donor conduit for drawing and returning whole blood to a donor; flow-through separation means for separating a desired blood fraction from whole blood; a fluid reservoir; a first fluid conduit connecting said donor conduit assembly, said separation means and said reservoir; a second fluid conduit connecting said-reservoir and said donor conduit; inlet pump means for pumping fluid along said first conduit; return pump means for pumping fluid along said second conduit; and system control means responsive to the volume of fluid in said reservoir for rendering said return pump operative upon said reservoir volume exceeding a predetermined maximum level, and inoperative upon said reservoir volume falling below a predetermined minimum level.

Claim 42

A blood fractionation system comprising: a donor conduit for drawing and returning whole blood to a donor; flow-through separation means for separating a desired blood fraction from whole blood; a fluid reservoir; a first fluid conduit connecting said donor conduit assembly, said separation means and said reservoir; a second fluid conduit connecting said-reservoir and said donor conduit; inlet pump means for pumping fluid along said first conduit; return pump means for pumping fluid along said second conduit; and system control means responsive to the volume of fluid in said reservoir for rendering said return pump operative upon said reservoir volume exceeding a predetermined maximum level, and inoperative upon said reservoir volume falling below a predetermined minimum level.

Claim 43

A blood fractionation system as defined in claim 36 wherein said second pump means is operator-adjustable relative to said first pump means whereby upon operation of said second pump means a selected portion of the whole blood from said reservoir is caused to recirculate through said separation means.

Claim 44

A blood fractionation system as defined in claim 36 wherein said second fluid conveyance means are responsive to the weight of said intermediate reservoir.

Claim 45

A blood fractionation system as defined in claim 36 wherein the rates of said inlet and return pumps are operator-adjustable.

Claim 46

A blood fractionation system as defined in claim 36 wherein the volume of said first conduit is substantially equal to or greater than the volume of whole blood returned from said reservoir upon operation of said return pump.

Claim 47

A blood fractionation system as defined in claim 40 wherein said first conduit includes an in-line fluid mixing chamber upline of said separation means having a volume substantially equal to or greater than the volume of whole blood returned from said reservoir upon a single operation of said return pump.

Claim 48

A blood fractionation system as defined in claim 36 wherein said second fluid conveyance means include a bubble trap and fluid absence detector.

Claim 49

A blood fractionation system as defined in claim 36 wherein said separation means comprise a membrane type filter.

Claim 50

A blood fractionation system as defined in claim 43 wherein said membrane type filter is a hollow-fiber type filter.

Claim 51

A blood fractionation system for separating whole blood into cellular and non-cellular components, and collecting the components, wherein whole blood is alternately drawn and returned relative to a donor through a phlebotomy needle, said system comprising: means for monitoring the volume of the separated cellular component; and control means for commencing return of the separated cellular component to the donor when the volume of the collected cellular component reaches a predetermined maximum level, and for terminating the return of the cellular component when the volume of the collected cellular component reaches a predetermined minimum level.

Claim 52

A blood fractionation system for separating whole blood into cellular and non-cellular components, and collecting the components, wherein whole blood is alternately drawn and returned relative to a donor through a phlebotomy needle, said system comprising: means for monitoring the volume of the separated cellular component; and control means for commencing return of the separated cellular component to the donor when the volume of the collected cellular component reaches a predetermined maximum level, and for terminating the return of the cellular component when the volume of the collected cellular component reaches a predetermined minimum level.

Claim 53

A blood fractionation system as defined in claim 45 wherein said control means are responsive to the weight of the separated cellular component.

Claim 54

A blood fractionation system as defined in claim 46 wherein said control means include an electrical weight transducer providing an output signal indicative of the weight of the separated cellular component.

Claim 57

The method of blood fractionation described in claim 48 wherein said pumping in is continued during said pumping back.

Claim 58

The method of blood fractionation described in claim 49 including the additional step of adjusting the rate of pumping in to the rate of pumping back to establish recirculation through said separation means.